This invention relates generally to a system for air doffing a fibrous web from the working cylinder of a textile fiber-processing machine, such as a textile-carding machine.
A typical textile-carding machine includes a feed roll to which a mass of fibers are fed. The feed roll transfers the fibers to a lickerin roll, which then transfers the fibers to the carding roll. The carding roll is the primary fiber working member in the carding machine and serves to form the mass of fibers being worked into a relatively thin, sheet-like configuration known as a web. The web is subsequently physically removed from the carding roll with a doffer roll and is condensed into a rope-like configuration known as sliver. The sliver is then typically further worked and ultimately is formed into yarn by a spinning machine.
The present invention is drawn to the removal, "doffing," of the web from the carding roll and formation of the removed web into a sliver.
Various doffing and carding machine devices are known. U.S. Pat. No. 4,475,271, issued to Lovgren, et al, and U.S. Pat. No. 4,706,338, issued to Anspach, discuss the doffing of a rotating carding cylinder by means of an air stream. U.S. Pat. No. 3,256,569, issued to Draving, discloses air doffing between a carding cylinder and a perforated condensing cylinder.
U.S. Pat. No. 4,599,766, issued to Wirth, discloses use of a perforated housing for removing microdust in fiber being doffed from a cylinder by a doffing cylinder 4. U.S. Pat. No. 4,884,320, issued to Gasser, et al, shows use of a trough in connection with a take-off roller.
While the foregoing designs are known, there still exists a need for an air doffing system which will remove a fiber web from a carding roll and assist in the formation of the web into a sliver.